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The "moving wall" represents the time period between the last issue
available in JSTOR and the most recently published issue of a journal.
Moving walls are generally represented in years. In rare instances, a
publisher has elected to have a "zero" moving wall, so their current
issues are available in JSTOR shortly after publication.
Note: In calculating the moving wall, the current year is not counted.
For example, if the current year is 2008 and a journal has a 5 year
moving wall, articles from the year 2002 are available.

Terms Related to the Moving Wall

Fixed walls: Journals with no new volumes being added to the archive.

Absorbed: Journals that are combined with another title.

Complete: Journals that are no longer published or that have been
combined with another title.

Abstract

A complete three-dimensional Patterson synthesis of haemoglobin has been calculated, giving the distribution of vector density in thirty-one sections through the unit cell. The sections show certain concentrations of vector density which can be interpreted in terms of polypeptide chain structure. The following are the conclusions tentatively arrived at on the evidence described in this paper. The haemoglobin molecule resembles a cylinder of 57 angstrom diameter and 34 angstrom height, which consists of an assembly of polypeptide chains running parallel to the base of the cylinder. The chains show a short-range fold, with a prominent vector of 5 angstrom parallel to the chain direction. In addition to this the chains also contain a longer fold which may extend through the whole width of the molecule. This long fold may be due either to open chains folded backwards and forwards through the molecule or to closed loops of polypeptide chains. The average distance between neighbouring chains, or neighbouring portions of the same chain folded back on itself, is 10· 5 angstrom. The chains are arranged in four layers which are about 9 angstrom apart and correspond to the four layers of scattering matter described in a previous paper. The haem groups lie with their flat sides approximately normal to the chain direction.